Microsoft sold more than 8 million Kinect controllers since its launch only a few months ago, making it one of the fastest selling accessories in the story of gaming.
Apple is yet to launch anything close to the Kinect - although it did come achingly close to using technology from Primesense, the same Israeli company that provided Microsoft with the IP to build the Kinect (read CultofMac's account of why Primesense said no to Apple).
Motion Control looks set to come to Apple's portable devices (iPhone, iPad and iPod Touch) fairly soon as the company has already applied for a patent that will allow users to control a host of basic phone-related features simply by swiping their fingers on the front facing camera.
Obviously, this can be used in conjunction with the other motion sensors present in iOS devices but it would be interesting to see whether Apple puts motion control in the Apple TV (and other devices).
The Apple TV is cheap and would lend itself very well to being motion controlled similarly to how Microsoft controlled Zune at CES 2011 during Steve Ballmer's keynote speech. PrimeSense still owns the technology behind Kinect which means that it can license it to someone else.
Given the cookie points Microsoft has earned from Kinect's success and the developer's momentum behind the technology, one can envision that Apple may integrate a Kinect-like sensor and electronics into the Apple TV fairly easily and interface it with the iOS.